make an effort to funnel immunity in mucosal sites of pathogen

make an effort to funnel immunity in mucosal sites of pathogen entrance. disc4+ T cells. Conversely administering an MMP2 inhibitor or CCL7 during vaccine delivery restored recruitment of Ly6Chi monocytes to the lung and priming of CD4+ T cells. Our results pinpoint mechanisms that underpin vaccination against fungi at the respiratory mucosa. They also highlight host and microbial strategies that must be overcome to engineer fungal and other vaccines that induce respiratory mucosal immunity. Mucosal vaccination against respiratory brokers may require manipulation of host MMPs that alter chemokine signals needed to recruit Ly6Chi inflammatory monocytes and primary CD4+ T cells at the respiratory mucosa. RESULTS Fungal vaccination at the respiratory mucosa Subcutaneous (s.c.) injection of mice with a live attenuated strain engenders 100% survival against a lethal pulmonary challenge (Wüthrich et al. 2000 but inconsistent sterilizing immunity. Since the natural route of contamination is usually inhalation of spores we sought to enhance the vaccine’s efficacy by delivering it into the respiratory tract. All mice vaccinated i.n. (Wüthrich et al. 2000 or intratracheally (i.t.) (data not shown) were unable RAF265 (CHIR-265) to control contamination and died after pulmonary challenge. This scenario contrasts with that for in which primary pulmonary contamination induces protective immunity and resistance against lethal pulmonary challenge (Deepe and Seder 1998 Since these two fungal infections require cellular immunity for resistance we compared the priming of CD4+ T cells for each of them to uncover the reasons for failure vs. success in priming RAF265 (CHIR-265) of T cells at the respiratory mucosa. Th1 differentiation occurs fully after CD4+ T cells migrate to the lung (Rivera et al. 2006 Although i.t. vaccination with induced activated CD4+ T cells RAF265 (CHIR-265) (CD44+) cells in the lung Th1 cells failed RAF265 (CHIR-265) to accrue and <1% produced IFNγ (Fig. 1A). There were ≈1 0 less IFNγ+ CD4 T cells in the lung after i.t. vaccination with compared with induced a 1 0 increase in the number of IFNγ+ CD4 T cells in the lung upon mucosal vaccination with nearly 14% producing IFNγ whereas induced little increase. In contrast s.c. administration of as well as lead to marked growth of IFNγ+ cells during a recall response after challenge. Mice given s.c. had 100-fold more IFNγ+ cells than unvaccinated controls and over 7% of CD4+ T cells produced this cytokine (Fig. S1A). Physique 1 Mucosal vaccination induces poor Th1 differentiation of polyclonal and transgenic CD4+ cells in response to to vaccinate at the respiratory mucosa. First the vaccine may not induce proliferation of specific CD4+ T cells or promote their survival. Second it may RAF265 (CHIR-265) not induce differentiation of Ag-specific T cells in the draining MLN. Third Th1 CD4+ T cells may not be recruited from MLN into the lung airways. Last CD4 T cells may not fully differentiate or mature into Th1 cells in the lung. To distinguish among these possibilities and interrogate T cell priming growth differentiation and trafficking we generated a TCR tg mouse specific for 1807 TCR tg mouse was designed (Fig. S1C-F; see supplemental experimental procedures) from MGC11337 a CD4+ T cell clone that confers protective immunity against lethal pulmonary challenge in mice (Wüthrich et al. 2007 1807 mice have an increased prevalence of Vα2+ CD4+ T cells in the peripheral blood spleen and LNs vs. wild-type B6 mice (Fig. S1E). Na?ve CD4+ T cells from 1807 mice became activated and proliferated in..